Whether encoding strategy affects the list method directed forgetting is a focus which the researches pay attention to.The paper continues to explore directed forgetting by introducing the instruction(remember,forget)and encoding strategy(no encoding strategy,shallow encoding strategy,deep encoding strategy)variable,using nouns of low frequency as the materials.The results show:(1)encoding strategy affects the list method directed forgetting.The cost of list method directed forgetting is significant,and the benefit is faint;(2)the mechanism of the list method directed forgetting is retrieval inhibition.